Cell connector and method for contacting at least two galvanic cells - Patents.com

Abstract

The present invention relates to a cell connector (1) for connecting at least two conductors (2) and / or Litz wires (3) to one another, which consists of at least one substantially stripe-shaped element (4). The cell connector (1) of the invention is characterized by at least five sections (4.1, 4.2, 4.3, 4.4, 4.5) arranged successively in the longitudinal direction (L) of the stripe-shaped element (4), in which the first section (4.1) forms a first half (5.1) of the closure element, the second section (4.2) forms a first clamping surface (6.1), the third section forms a bent element (7), the fourth section (4.4) forms a second clamping surface (6.2), the fifth section (4,5) forms a second half (5.2) of the closure element, and the third section (4.3) forms a first half (5.1) of the closure element, the second section (4.2) forms a first clamping surface (6.1), the third section (4.4) forms a second clamping surface (6.2), the fifth section (4,5) forms a second half (5.2) of the closure element, and the third section (4.3) forms a second half (5.2) of the closure element, in which the first section (4.1) and the second section (4.2) form a second clamping surface (6.3). , the fourth section (4.4) and the fifth section (4.5), so that in the folded state of the stripe-shaped element (4), at least a part of the first clamping surface (6.1) and the second clamping surface (6.2) face each other, thereby forming a receiving portion (9) for the conductor (2) and / or the Litz wire (3), and the first section (4.1) and the fifth section (4,5) are connectable to each other in order to fix the at least one stripe-shaped element (4) in the folded state, when the stripe-shaped element (4) is in the folded state.

Description

[Technical Field]

[0001] The present invention provides at least one Band-shaped The present invention relates to a cell connector for connecting at least two conductors and / or Litz wires to one another, which comprises an element, as well as to a method for contact-connecting at least two galvanic cells with at least one such cell connector. [Background technology]

[0002] Galvanic cells, also referred to as battery cells, are devices that convert chemical energy into electrical energy. Such galvanic cells can also be used to supply electrical energy to mobile devices. Various embodiments of galvanic cells and battery modules consisting of several galvanic cells connected to one another are known from the general prior art. For example, to boost the voltage output by a galvanic cell, individual galvanic cells can be connected in series. To increase the capacity of a battery module consisting of several galvanic cells, several galvanic cells connected individually or in series can also be connected in parallel. The electrical connection of the individual galvanic cells is carried out here via corresponding contact elements. In particular, in the case of so-called pouch cells, aluminum or copper conductors are used for this purpose.

[0003] To securely connect conductors, they are welded. Such connections require a minimum cross-section because relatively large currents are transmitted through the conductors and thus through the corresponding connection points. If the cross-section is too small, the connection points may heat up so much that damage or destruction of individual components of the pouch cell and / or battery module is a risk. Ensuring high process reliability when forming welded connections between multiple conductors requires overcoming several challenges. For example, the two conductors to be connected must abut against each other over as large an area as possible. This is because insufficient contact between the two conductors can result in gaps between the conductors after welding. Therefore, the conductors to be connected are often pressed together before the welding process using spring-loaded clamping fingers, clamping frames, or the like to adjust the gap between the conductors. Here, the cell frame is often used as the mating receiving part. Nevertheless, due to tolerances when bending conductors and stacking galvanic cells, gaps can form between the conductors to be connected due to shifting of the galvanic cells during transportation, as well as due to incorrect setting of the clamping force of the clamping device. Furthermore, the clamping force cannot be selected arbitrarily large, because the maximum clamping force is limited by the stability or strength of the cell frame.

[0004] Typically, the first conductor of a conductor pair to be welded comprises aluminum or an aluminum alloy, and the second conductor comprises copper or a copper alloy. This establishes a material-bonding connection between two dissimilar materials. Selecting and maintaining the correct welding parameters is therefore particularly challenging. For example, there is a significant risk of weld penetration from the conductor into the cell frame. When multiple galvanic cells are connected in parallel, multiple layers of conductors are welded together, which can result in cumulative tolerances and stacking errors.

[0005] Typically, the conductors of the pouch cells are connected by laser welding. Other welding methods, such as ultrasonic welding, can also be applied, but they have inherent drawbacks. For example, ultrasonic welding requires accessibility to the workpieces to be welded from both sides and a large space for pulling the workpieces. Therefore, ultrasonic welding equipment is relatively large. In addition, the electrodes used for welding are subject to wear. Furthermore, the conductors to be connected may stick to the welding electrodes.

[0006] Furthermore, it is known to connect a plurality of galvanic cells in parallel by means of so-called cell connectors, which are made of, for example, metal. Band-shaped If the galvanic cells to be connected have a height misalignment with one another, the cell connector will abut obliquely on the conductors to be connected, resulting in only point or linear contact between the cell connector and the conductor. This reduces the cross-sectional area of ​​the electrical contact of the galvanic cells to be connected. To compensate for this height misalignment, such cell connectors can be curved along at least one section. However, this creates the problem of accurately positioning the cell connector to ensure a weld seam of sufficient quality. The greater the number of cells to be connected with the cell connector, the more serious the problems resulting from the height misalignment can become. For example, in a single cell, the height misalignment can be so great that a gap forms between the conductor and the cell connector. In addition, it is known to provide openings in the cell connector for guiding the conductors through. However, this requires the conductors to be threaded through the cell connector, which places a mechanical load on the conductors and may damage them. In addition, there is a risk that the laser beam will hit the galvanic cells to be contacted. To avoid this, strict requirements are placed on the positioning of the galvanic cells or conductors to be connected and the cell connectors in the laser welding machine.

[0007] Furthermore, Patent Document 1 discloses a method for contacting electrical terminals with battery conductors. In many electronic devices, batteries are connected to the electronic device's electrical circuitry by welding or brazing. However, due to the limited construction space available within the electronic device, the corresponding welding or brazing points are difficult to access. The method disclosed in this reference describes molding metal strips onto the conductors of a battery cell, which increases the area and improves accessibility, allowing the conductors to be easily contacted by additional current-carrying components or electrical terminals. For each conductor, the metal strip is placed flat on the conductor and curved around it, so that it surrounds the conductor as widely as possible. The resulting layer structure consisting of the conductor and metal strip is then placed in an ultrasonic welding machine, where the individual layers are connected by ultrasonic welding. The layer structure, secured by welding, is then cut to size. [Patent Document 1] US 6,641,027 B2 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention is based on the object of providing a cell connector for connecting at least two conductors and / or Litz wires to one another, which cell connector ensures that the conductors or Litz wires to be connected are aligned with one another, thereby enabling a reliable welded connection to be established between the conductors and / or Litz wires to be connected with reduced effort.A further object of the present invention is to provide a method for contact-connecting at least two galvanic cells by means of at least one such cell connector. [Means for solving the problem]

[0009] According to the invention, these problems are solved by a cell connector having the features of claim 1 and a method for contacting at least two galvanic cells having the features of claim 10. Advantageous embodiments and developments are evident from the dependent claims.

[0010] At least one abbreviation Band-shaped According to the invention, a cell connector for connecting at least two conductors and / or Litz wires to one another is provided, which consists of the element: Band-shaped The closure has at least five sections arranged consecutively in the longitudinal direction of the element, where the first section forms a first half of the closure element, the second section forms a first clamping surface, the third section forms a bending element, the fourth section forms a second clamping surface, and the fifth section forms a second half of the closure element. The third section is configured to allow the first and second sections to be folded relative to the fourth and fifth sections about a folding axis extending through the third section in a width direction extending perpendicular to the longitudinal direction. This allows the closure to be folded relative to the fourth and fifth sections about a folding axis extending through the third section in a width direction extending perpendicular to the longitudinal direction. Band-shaped The element is movable into a folded state in which at least a portion of the first clamping surface and the second clamping surface are substantially opposed in a thickness direction extending perpendicular to the longitudinal and width directions, thereby forming a receiving portion for the conductor and / or Litz wire. Band-shaped In the collapsed state of the element, at least one Band-shaped The elements are connectable to one another to secure them in the folded state.

[0011] With the cell connector of the invention, a particularly reliable mutual adjustment and fixation of the conductors and / or Litz wires to be connected is possible, which increases the process reliability for the material-bonded connection of the conductors and / or Litz wires in the welding process following the mutual adjustment. Band-shaped By folding the element (hereinafter referred to as "closing"), the conductors and / or Litz wires to be connected are pressed together, thereby compensating for stacking tolerances. Band-shapedWhen the elements are closed, the conductors and / or Litz wires to be connected are fixed and cannot move relative to each other and therefore cannot separate from each other even during the transport process to the welding station. Band-shaped In the folded state, the element completely surrounds the receiving portion. Therefore, the fourth section or the second clamping surface forms a substrate or base material for the laser welding process, which makes full penetration welding through the conductors and / or litz wire difficult. The second section or the first clamping surface is positioned between the conductors and / or litz wire to be connected and the laser light source during the laser welding process, and thus serves as a material reservoir. Therefore, the second section can also be melted and incorporated into the material-bonding connection between the conductors and / or litz wire to be connected. This allows potential gaps to be filled. Furthermore, by selecting the appropriate material, the welded connection can be appropriately alloyed.

[0012] Furthermore, the use of the cell connector of the present invention can reduce the manufacturing costs for contacting multiple galvanic cells via conductors. For example, the need for tedious adjustment of the clamping tool used to press the conductors to be connected together is eliminated. The conductors to be connected are pressed together particularly easily and reliably using the cell connector of the present invention. This also allows for flexible connection of different cell shapes to one another, since there is no need to change the clamping technique used to press the conductors together. Correspondingly, flexible laser cabins of various types and versions are conceivable. This also reduces the programming costs of the laser welding machine used to weld the conductors and / or Litz wires to be connected. Since the weld seams are not covered by complex clamping techniques, the resulting weld seams can be more easily inspected. Furthermore, the cell connector of the present invention can be manufactured particularly simply and inexpensively. Therefore, the cell connector is, for example, a simple plate-bent punched part. The cell connector of the present invention in an advantageous embodiment can also be punched from a single plate.

[0013] An advantageous development of the cell connector provides that the third section comprises at least one perforation, a hinge and / or an elastic material and / or is at least partially contoured. The third section is used to allow bending or folding of the individual sections of the cell connector in order to close or bring at least one substantially strip-shaped element into a folded state. By introducing perforations into the third section, the bending stiffness of the third section is reduced, thereby making it possible to close the substantially strip-shaped element. Band-shaped The element can be bent particularly easily around the folding axis. The perforations can be configured in any way. For example, they are one or more rectangular punched sections. However, the punched sections can also have any shape. Thus, the punched sections or perforations can be embodied in the shape of, for example, an oval, a circle or any polygon. In addition to or instead of the perforations, hinges can also be incorporated or formed in the third section. A two-part hinge allows for the connection of at least two approximately Band-shaped The elements can be connected together to form a cell connector. Band-shaped The element includes a first and a second interval, and the second abbreviation Band-shaped The element includes a fourth and a fifth section. For example, the third section may have or be formed by a film hinge. Additionally or alternatively, the third section may include a resilient material. For example, the third section may include a rubber, elastomer, etc. Resilient materials are particularly easy to bend, stretch, and compress, so at least one approximately Band-shaped The element can be moved into the folded state particularly easily. The joint can also be integrated into or formed in the third section. Additionally or alternatively, the third section can be contoured. For example, the third section can be configured like a cover for the joint of an accordion or a jointed bass. This means that at least one Band-shapedThis makes it easier to fold or bend the individual sections of the element. The contouring here can be implemented in any way, and in particular can have any orientation in the third section. For example, the contouring preferably extends in the longitudinal direction. This ensures a certain minimum bending stiffness in the width direction and reduces the bending stiffness around the folding axis. Therefore, at least one approximately Band-shaped The element can be moved particularly easily into the folded state, preventing or reducing tilting of the opposing sections, which ensures that the second and fourth sections or the first and second clamping surfaces remain as parallel as possible to one another in the folded state, thereby increasing the reliability of the crimping of the conductors and / or Litz wires to be connected.

[0014] Corresponding to a further advantageous embodiment of the cell connector, the first and fifth sections are designed for a positive connection, in particular by bending, beading, rolling or crimping at least one of the sections, and / or the first and fifth sections are designed for a frictional and / or material connection, in particular by riveting, screwing, welding and / or gluing the sections together, whereby the first and fifth sections can be fixed particularly reliably. Band-shaped This reliably prevents the element from unintentionally opening up from the folded state. In particular, the first and fifth sections have geometric shapes that suit each other accordingly, which makes it particularly easy to connect these sections. For example, the first section can be embodied as a tab, and the fifth section as a pocket for receiving the tab. The tab can thus be folded into the pocket, which makes it particularly easy to connect the first and fifth sections to each other. In addition, this connection can be fixed, for example, by crimping. It is also possible to fix the form-locking connection between the first section and the fifth section, for example, by brazing the two sections. In general, at least one approximately Band-shapedThe elements can be secured in the folded state by overlaying or otherwise securing with additional clamping means, e.g., a relatively thin elastic band, approximately Band-shaped A cover can be placed over the element, for example, shrink tubing can be used for this purpose.

[0015] A further advantageous embodiment of the cell connector further provides that the second section has a cutout, particularly a substantially rectangular cutout, for forming a welding window, extending completely through the second section in the thickness direction, with the long side of the cutout extending in the longitudinal direction. Introducing a cutout into the second section or the first clamping surface allows the laser of the laser welding machine to directly access the conductors and / or Litz wires to be connected. This eliminates the need to weld through the second section or the first clamping surface. This reduces the thermal load on the elements to be connected. Furthermore, higher welding speeds and / or lower laser powers can be achieved. Additionally, the resulting weld seam can be more easily visually inspected. By extending the cutout or welding window, particularly substantially longitudinally, the long side of the cutout preferably coincides with the selected weld seam direction. It is also conceivable to implement the cutout in an interrupted manner, so that individual sections of the resulting weld seam can be separated approximately. Band-shaped The materials of the elements can be alloyed by melting them. This allows the electrical conductivity and / or mechanical load-bearing capacity of the weld seam to be more appropriately adjusted. Similar to the perforations introduced into the third section, the notches for forming the welding windows can also be introduced into the second section, for example, by punching the notches. However, it is also possible to cut the notches, for example, from the second section, for example, with a laser beam or a water jet.

[0016] According to a further advantageous embodiment of the cell connector, at least two longitudinally parallel arranged Band-shaped The element is separated widthwise from the second and / or fourth section. Band-shapedThe elements are connected via at least one web extending away from the elements and extending in the longitudinal direction. Using such a cell connector, individual galvanic cells and / or cells connected in series can be connected in parallel particularly simply and reliably. The web here can have any shape. In particular, the web extends in the longitudinal direction over the entire length of the second and / or fourth section. This increases the cross-sectional area of ​​the web in the width direction, thereby reducing the thermal load on the web due to relatively large currents. In particular, the web, viewed in the thickness direction, has a cross-sectional area of ​​approximately Band-shaped It has the same material thickness as the remaining sections of the element, which makes it particularly easy to produce the corresponding cell connectors, which can also be punched or cut out of the plate.

[0017] In a further advantageous embodiment of the cell connector, it is provided that the web has at least one perforation, in particular the web has a thickness direction of approximately Band-shaped The web has a thickness smaller than that of the elements and / or is corrugated in the width direction, which makes it easier to compensate for height deviations of the galvanic cells arranged side by side and connected by the cell connector of the present invention. Band-shaped The elements can be easily moved relative to one another in the thickness direction. The corresponding stiffness of the web can be further reduced by reducing the thickness of the web in the thickness direction. The cross-sectional shape of the web as viewed in the longitudinal direction can also have a corresponding contour, for example a corrugated cross section, in order to more easily compensate for height deviations between the individual, generally strip-shaped elements of the cell connector in the thickness direction.

[0018] In accordance with a further advantageous embodiment of the cell connector, at least one Band-shaped The element has a connecting flange extending longitudinally and extending widthwise away from the second and / or fourth section, the connecting flange being approximately Band-shaped The current-carrying components placed on top of the element are Band-shapedThe cell connector of the present invention has a connecting flange for contacting elements. Using this connecting flange, the cell connector of the present invention can be easily contacted to, for example, a current contact rail. This also allows a particularly easy circuit connection of several battery modules or cell blocks with one another. Here, the connecting flange, like the first or fifth section, can have a shape that is specifically adapted to a specific installation situation or geometric situation. For example, one or more through-holes can be introduced into the connecting flange to allow the connecting flange to be screwed to the current contact rail. Here, the current can flow via a screw guided through the through-hole. In general, it is conceivable that any form-fitting, friction-fitting, and / or material-fitting connection can be established between the at least one connecting flange and the at least one superposed current-carrying component. For example, the connecting flange can be welded or riveted to the current contact rail. Advantageously, the connecting flange can be attached to several approximately the same components included in the cell connector. Band-shaped One abbreviation on the edge of the element Band-shaped Included in the element.

[0019] In a further advantageous embodiment of the cell connector, in order to increase the pressing force of the first and second clamping surfaces acting in the thickness direction on the conductor and / or Litz wire arranged in the receiving part, at least one approximately Band-shapedIt is contemplated that the second section is at least partially curved in the thickness direction when the element is folded, and / or that at least one half of the closure element has a contour extending in the thickness direction when the closure element is connected. Preferably, the conductors and / or Litz wires to be connected are pressed together with a relatively large pressure to securely fasten them together. The curvature of the second section increases this pressure due to the spring action of the second section resulting from the curvature. Here, the entire second section may be curved, or may at least partially have individual curvatures. The individual curvatures may have the same or different radii of curvature. In addition to or instead of the curvature of the second section, one or both halves of the closure element may also have a contour extending in the thickness direction. These may have any cross-sectional shape. For example, this may be a conical or pyramidal tip. At least one half of the closure element may also be partially corrugated in the thickness direction. The contour requires that the first and second sections be further folded about the folding axis until the first and fifth sections can be closed, thereby reducing the distance between the first and second clamping surfaces in the thickness direction and thereby increasing the pressing force on the conductor and / or Litz wire present in the receiving portion.

[0020] Preferably, at least one abbreviation Band-shaped The element may be made entirely of an electrically conductive material, in particular a metal and / or metal alloy, preferably a metal plate, or may have at least one substantially Band-shaped The element is at least partly made of an electrically conductive material, in particular a metal or metal alloy, preferably a metal plate, and at least partly made of a current insulating material, which insulating material advantageously forms at least the fourth section. Band-shaped If the element comprises a conductive material, the current between the conductors and / or Litz wires to be connected can also flow at least partially through at least one substantially strip-shaped element. Band-shaped By means of the element, for example, a parallel connection of several galvanic cells can be realized in a particularly simple manner. Band-shaped If the element comprises a metal or metal alloy, then for example the second section can also be welded into a material-bonding welded connection of the conductors and / or Litz wires to be connected.

[0021] Cell connectors have at least two Band-shaped If it consists of elements, the first abbreviation Band-shaped The element includes a first and a second interval, and the second abbreviation Band-shaped It is also possible that the element includes a fourth and fifth interval, in which case the first abbreviation Band-shaped The element is made entirely from a metal alloy, and the second abbreviation Band-shaped The element is made of an insulating material. If the fourth section, i.e., the second clamping surface, comprises an insulating material, this material can serve as a weld bead support. On the other hand, if the fourth section also comprises metal or a metallic material, it can also be welded, which ensures a process-reliable contact connection of the conductor and / or Litz wire.

[0022] Generally, it is conceivable that the entire cell connector is made from insulating material.

[0023] A method for contacting at least two galvanic cells by means of at least one cell connector as described above comprises, according to the invention, at least the following method steps: - mutual adjustment of the conductors and / or Litz wires to be connected; positioning the cell connector relative to the conductors and / or Litz wires in such a way that the fourth section is at least partially supported on the cover of the at least one galvanic cell opposite the receiving part and / or the at least one conductor and / or the at least one Litz wire rests on the side of the fourth section facing the receiving part; · Band-shaped folding the first section and the second section with a folding axis extending widthwise through the third section to place the element in a folded state; closing the closure element; welding the conductors and / or Litz wires to be connected or welding at least a part of the cell connector to the conductors and / or Litz wires to be connected, in particular by means of at least one longitudinally extending weld seam, preferably using laser welding as welding method, is executed.

[0024] The conductors and / or Litz wires to be connected are adjusted to each other so that they contact or overlap over as large an area as possible, enabling a low-resistance contact connection of the galvanic cells to be connected. The conductors and / or Litz wires to be connected are then fixed in place using the cell connector of the present invention. For this purpose, the cell connector of the present invention is guided around the conductors and / or Litz wires to be connected and closed, like a clamp. Optionally, the cell connector of the present invention can be supported on the cover of the at least one galvanic cell or the battery module and / or battery housing containing the galvanic cell. Preferably, the at least one conductor and / or the at least one Litz wire is placed flat on at least one of the clamping surfaces. This ensures that a particularly uniform pressure is applied to the conductors and / or Litz wires to be connected. The closure of the closure element is achieved by any form-locking, friction-locking, and / or material-locking mechanism. For example, individual parts of the closure element halves, such as tabs or protrusions, can be folded, crimped, rolled up, etc., so that they can be introduced or received into the corresponding counterpart closure element halves, for example, through openings or receiving sections. The closed closure element can be additionally secured by riveting, screwing, welding, brazing, gluing, etc. The galvanic cell to be contacted can then be safely transported without the conductors and / or Litz wires to be connected shifting or slipping during transport, because the pressing force exerted on the conductors and / or Litz wires by the cell connector of the present invention prevents this. The conductors and / or Litz wires to be connected are then welded. Any welding method, preferably laser welding, can be used for this purpose. Because the conductors and / or Litz wires are pressed by the cell connector of the present invention, a particularly reliable welded connection can be formed.

[0025] Further advantageous embodiments of the cell connector according to the invention and the method according to the invention can be seen from the detailed examples which are explained below with reference to the figures. [Brief explanation of the drawings]

[0026] [Figure 1] 1A-1C are diagrams showing the principle of four known variants for connecting multiple pouch cells to each other. [Figure 2] 1A and 1B are plan and side views of a cell connector of the present invention, and two detailed views of the third section of the cell connector of the present invention. [Figure 3] FIG. 10 is a plan view of a cell connector of the present invention according to an alternative embodiment. [Figure 4] 1 is a plan view of a cell connector of the present invention comprising a plurality of roughly strip-shaped elements. [Figure 5] 10A and 10B are plan and side views of a cell connector of the present invention according to an alternative embodiment. [Figure 6] FIG. 6 is a detailed view of the cross section BB shown in FIG. 5. [Figure 7] 10 is a plan view of a cell connector of the present invention comprising a plurality of generally strip-shaped elements according to an alternative embodiment. FIG. [Figure 8] FIG. 8 is a detailed view of the CC cross section shown in FIG. 7. [Figure 9] 10 is a plan view of a cell connector of the present invention according to an alternative embodiment, with a connection flange. FIG. [Figure 10] 1 shows a principle diagram of the method according to the invention for contacting at least two galvanic cells; [Figure 11] FIG. 11 is a detailed view of the cross section DD shown in FIG. 10. [Figure 12] 1 is a side view of a laser welding process for contacting two electrical cables with a cell connector of the present invention. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0027] FIG. 1 is used to explain the problems encountered in the prior art when connecting a plurality of so-called pouch cells 19 to one another. Here, FIG. 1a) illustrates the problem when the pouch cells 19 are connected in series, and FIG. 1b) illustrates the problem when several pouch cells 19 are connected in parallel. To connect at least two pouch cells 19 in series, the conductors 2, often made of copper or aluminum, leading out of the pouch cells 19 are welded together. This preferably ensures that the conductors 2 to be connected contact each other flatly and along as large a distance as possible. Due to deflection errors and / or component tolerances during the mutual adjustment of the conductors 2 to be connected, the conductors 2 to be connected do not run parallel but at an angle to one another, so that they do not contact each other flatly but only along a line or even at points. In this case, the continuous weld seam 18 shown in FIG. 11 cannot be formed to connect the two conductors 2, or a defective weld seam 18 would result.

[0028] To compensate for such deflection errors or component tolerances, the conductors 2 to be connected are pressed together by applying a pressing force F using a press tool 20. This is shown on the right in FIG. 1a). This causes the conductors 2 to be flat against one another and allows for reliable welding. Typically, a cover 17 of at least one of the pouch cells 19 is used as a support. This cover 17 can be, for example, the cell frame of one of the pouch cells 19 or the battery module housing. The disadvantage here is that deflection errors cannot be completely compensated for, and therefore the gap between the conductors 2 to be connected cannot be reduced to zero. Furthermore, the corresponding press tool 20 must be adjusted tediously.

[0029] Another problem is connecting multiple pouch cells 19 to form a parallel connection. For this purpose, cell connectors 21 known from the prior art are typically used. If the parallel-connected pouch cells 19, their covers 17, or the cell frames of the pouch cells 19 have a height misalignment with one another, this can result in the cell connector 21 abutting obliquely against the conductors 2 to be connected. This, in turn, creates gaps, preventing the cell connector 21 from being welded flush to the conductors 2 to be connected. To compensate for this height difference, cell connectors 21 with curved sections are known. This is shown on the right in FIG. 1b. However, this places relatively high demands on the precise positioning of the components to be connected during the welding process. This problem can become even more severe when connecting more than two pouch cells 19 in parallel.

[0030] By using the cell connector 1 shown in Fig. 2, the pouch cells 19 to be connected or contacted can be particularly reliably contacted by welding. Band-shaped The element 4 includes five sections 4.1, 4.2, 4.3, 4.4, 4.5, which are arranged successively in the longitudinal direction L, approximately Band-shaped It is located in element 4. Band-shaped The element 4 has a dimension in a thickness direction D perpendicular to the longitudinal direction L and the width direction B that is smaller than the dimension in the longitudinal direction L and the width direction B perpendicular to the longitudinal direction L. The first section 4.1 and the fifth section 4.5 form half of the closure elements 5.1 and 5.2, respectively. The second section 4.2 forms the first clamping surface 6.1, and the fourth section 4.4 forms the second clamping surface 6.2. The third section 4.3 forms the bending element 7. A folding axis 8 extends through the bending element 7 in the width direction B. Approximately Band-shaped The element 4 can be folded or closed around a folding axis 8. Band-shapedTo allow relatively easy bending or folding of the element 4 around the folding axis 8, the bending stiffness of the bending element 7 is reduced by providing perforations 10 in the bending element 7 or in the third section 4.3. The perforations 10 here can be formed by rectangular cutouts, as shown in FIG. 2. However, the perforations 10 can have any shape. In addition to or instead of the perforations 10, the bending element 7 can also include or be formed by a hinge 11. This is shown in detail view A. If the hinge 11 forms the third section 4.3, the cell connector 1 of the invention can have at least two approximately Band-shaped It is composed of four elements. In this case, each abbreviation Band-shaped The elements 4 can also be made of the same or different materials. Band-shaped One of the elements 4 is made of a conductive material M as shown in FIG. Band-shaped The element 4 can be made from a current insulating material I. In general, however, the entire cell connector 1 can be made only from a conductive material M or only from an insulating material I. The cell connector 1 can also be made from a conductive material, in which case it is approximately Band-shaped One of the elements 4 is made of a first conductive material M, for example aluminum, and the second is made of a Band-shaped The element 4 is made of another electrically conductive material M, for example, copper. FIG. 2 shows a further detail A, in which, instead of the hinge 11, an elastic material 12 is shown for forming the third section 4.3. In this case, this may be, for example, an elastomer. However, any elastic material, such as rubber, natural rubber, silicone, etc., is conceivable for forming the third section 4.3. In particular, the third section 4.3 or the bending element 7 may also be at least partially perforated. This allows for an appropriate adjustment of the bending resistance around the folding axis 8 or around the longitudinal direction L. The third section 4.3 may also comprise the electrically conductive material M, in particular in the form of a film hinge.

[0031] The first section 4.1 and the fifth section 4.5 or the respective halves 5.1 and 5.2 of the closure element here have geometric shapes that fit together. In the example of FIG. 2, the first section 4.1 forms a tab and the fifth section 4.5 forms a pocket for receiving the tab. Band-shaped When the element 4 is folded about the folding axis 8, the respective closure element halves 5.1 and 5.2 are adjusted to one another so that they form a positive fit. To secure the positive fit, the respective closure element halves 5.2 and 5.2 can be joined by an additional frictional and / or material bond.

[0032] 3 shows a plan view of an alternative embodiment of the cell connector 1 of the present invention, in which the second section 4.2 or the first clamping surface 6.1 is provided with a substantially rectangular cutout for forming a welding window 13. However, the welding window 13 can also have any shape different from a rectangle. The welding window 13 improves the accessibility of a welding tool to the conductors 2 and / or Litz wires 3 surrounded by the cell connector 1, as shown in FIGS. 10 and 11.

[0033] Figure 4 shows multiple abbreviations Band-shaped 1 shows a plan view of a cell connector 1 of the present invention with elements 4, in which several abbreviated Band-shaped The elements 4 are connected to each other via one web 14. In the example of FIG. 4, each of the webs 14 is approximately Band-shaped It is connected to the second section 4.2 of element 4. Here, Band-shaped One or more of the elements 4 may also have a welding window 13. In this case, approximately Band-shaped It is not necessary that all bending elements 7 of an element 4 are configured identically. Band-shaped The element 4 may have, for example, perforations 10, hinges 11 and / or elastic material 12 for forming the bending element 7. Generally, however, at least one web 14 is approximately Band-shapedIt is also conceivable that it is at least partially connected to the fourth section 4.4 of one of the elements 4. By means of the cell connector 1 shown in Figure 4, several galvanic or pouch cells 19 can be circuit-connected in parallel with one another in a particularly simple manner.

[0034] In the closed or folded state, Band-shaped The element 4 surrounds the two conductors 2 and / or the Litz wire 3 to be connected. Band-shaped The element 4 exerts a pressure force F on the components to be connected. To increase this pressure force F, as shown in FIG. Band-shaped At least one region of any one section of the element 4 can be curved. In the example of FIG. 5, the entire second section 4.2 is curved around the width direction B. The resulting elastic effect allows the pressing force F to be increased. Band-shaped It is also conceivable that several sections 4.1 to 4.5 of the element 4 are curved or have only partially curved regions.

[0035] The pressing force F can also be increased by contouring the first and / or second closure element halves 5.1 and 5.2. To this end, FIG. 6 shows a detailed view of the cross section BB shown in FIG. 5. The contour 22 here can have any shape. For example, the contour 22 can be formed by a conical or pyramidal stump protruding in the thickness direction D. The closure element half 5.1 or the closure element half 5.2 can also have a wavy cross section in the width direction B.

[0036] FIG. 7 illustrates a schematic diagram of a plurality of Band-shaped 7 shows a plan view of a cell connector 1 of the present invention with element 4. In the example of FIG. 7, the perforations 15 are arranged in two approximately Band-shaped The perforations 15 are provided in the web 14 connecting the elements 4. The perforations 15 reduce the bending stiffness of the web 14 in the longitudinal direction L. This makes it easier to compensate for height deviations in the thickness direction D when connecting two pouch cells 19 in parallel. Again, the perforations 15 can have any cross-sectional shape. Preferably, the perforations 15 have a rectangular shape.

[0037] Figure 8 shows a detailed view of cross section CC shown in Figure 7. By reducing the material strength in the material portion of the web 14, the bending stiffness of the web 14 can be appropriately adjusted to a desired value. The web 14 can also have a specific cross-sectional shape in the width direction B, for example, a wavy cross-sectional shape.

[0038] 9 shows a plan view of a cell connector 1 of the present invention according to a further alternative embodiment. Band-shaped The element 4 has a connecting flange 16, which extends away from the second section 4.2 and / or the fourth section 4.4 in the width direction B. By using the connecting flange 16, approximately Band-shaped The element 4 can be simply and reliably contact-connected to a current-carrying component arranged thereon, such as a current contact rail or a conductor of a battery module, where the connection flange 16 can be connected to the current-carrying component arranged thereon in any manner and form, with a positive, frictional and / or material connection. Band-shaped Two through holes are introduced into the connection flange 16 in order to connect the element 4 to an overlying current-carrying element by means of a screw connection. If metal screws are used, the current can be passed through the screws. However, the connection flange 16 can also be welded, brazed or riveted to the overlying current-carrying component. Corresponding structural modifications can also be made to the connection flange 16, for example, in order to insert the connection flange into the overlying current-carrying component.

[0039] 10 shows a principle diagram of a method 100 according to the invention for contact-connecting at least two galvanic cells, for example two pouch cells 19. In method step 101, the conductors 2 and / or Litz wires 3 (not shown here) to be connected are aligned with one another so that they overlap as evenly as possible, thereby forming a particularly reliable weld seam 18. In method step 102, a wire 18 is welded, which may optionally be pre-bent, approximately. Band-shapedThe cell connector 1 of the present invention, consisting of the element 4, is pressed between the conductors 2 to be connected and the cover 17 of the pouch cell 19 or the frame of the battery module. Band-shaped The element 4 is folded around the folding axis 8 so that the first and second clamping surfaces 6.1 and 6.2 lie flat on the conductor 2 or Litz wire 3 to be connected and press them together with a pressing force F. In doing so, at least one approximately Band-shaped The element 4 forms a receiving section 9 for receiving the components to be connected. In the folded state, the first half 5.1 of the closure element and the second half 5.2 of the closure element are connected to each other in at least one approximately folded state. Band-shaped The element 4 is connected to prevent it from opening undesirably. The pouch cell 19 to be contacted is then transported to a welding device. Thanks to the closed cell connector 1, the fixed components to be contacted, i.e., the conductors 2 and / or the Litz wires 3, cannot move relative to one another. In method step 104, the conductors 2 and / or the Litz wires 3 are welded. Laser welding is preferably used for this purpose.

[0040] FIG. 11 shows various cross-sectional views of the cross section DD shown in FIG. 10. Depending on the embodiment of the cell connector 1 used, four different weld seams 18 are generated. Here, FIGS. 11a and 11b show the weld seam 18 with a cell connector 1 without a welding window 13, while FIGS. 11c and 11d show the weld seam 18 when a cell connector 1 with a welding window 13 is used. Furthermore, FIGS. 11a and 11c show the application of a conductive material M to form the fourth section 4.4 or the second clamping surface 6.2. Thus, the weld seam 18 can extend into the second clamping surface 6.2. This is not possible in FIGS. 11b and 11d because the fourth section 4.4 or the second clamping surface 6.2 is made of a current-insulating material I. This allows the cell connector 1 to function as a weld bead support. On the other hand, if the weld seam 18 penetrates into the fourth section 4.4, a particularly process-reliable contact connection of the conductors 2 and / or litz wires 3 to be connected can be ensured. In the example of FIGS. 11a) and 11b), welding of the second section 4.2 also allows the weld seam 18 to be suitably alloyed. Generally, in the embodiment of FIG. 11d), the entire cell connector 1 can also consist of the current-insulating material I. Nevertheless, the weld window 13 ensures weldability of the conductors 2 and / or litz wires 3 to be connected.

[0041] Figure 12 shows a side view of a laser welding process for contacting two electric cables by means of the cell connector 1 of the invention. Figure 12 is used to explain that instead of at least one conductor 2, one or more Litz wires 3 of one or more conducting cables can also be fixed according to one of the above-described embodiments in order to make them particularly reliably weldable.

Claims

1. A cell connector (1) for connecting at least two conductors (2) and / or Litz wires (3) to each other, comprising at least one strip-shaped element (4), The strip-shaped element (4) is characterized by at least five sections (4.1, 4.2, 4.3, 4.4, 4.5) arranged successively in the longitudinal direction (L) of the strip-shaped element (4), wherein a first section (4.1) forms a first half (5.1) of the closure element, a second section (4.2) forms a first clamping surface (6.1), a third section forms a bending element (7), a fourth section (4.4) forms a second clamping surface (6.2), and a fifth section (4.5) forms a second half (5.2) of the closure element, the third section (4.3) being arranged in a width direction (B) extending perpendicular to the longitudinal direction (L) with respect to the first section (4.1) and the second section (4.2), and the fourth section (4.4) and the fifth section (4.5). and the third section (4.3) is configured to allow the strip-shaped element (4) to be folded around a folding axis (8) extending through the third section (4.3), so that, in the folded state of the strip-shaped element (4), at least a portion of the first clamping surface (6.1) and the second clamping surface (6.2) are substantially opposite each other in a thickness direction (D) extending perpendicular to the longitudinal direction (L) and the width direction (B), thereby forming a receiving portion (9) for the conductor (2) and / or Litz wire (3); and the first section (4.1) and the fifth section (4.5) are connectable to each other in order to fix the at least one strip-shaped element (4) in the folded state, in the folded state of the strip-shaped element (4). The cell connector (1) comprises at least two strip-shaped elements (4) arranged parallel to each other in the longitudinal direction (L), which extend from the second section (4.2) and / or the fourth section (4.4) in the width direction (B) away from the strip-shaped elements (4) and are connected via at least one web (14) extending in the longitudinal direction (L).

2. 2. The cell connector (1) according to claim 1, characterized in that the third section (4.3) comprises at least one perforation (10), a hinge (11) and / or an elastic material (12) and / or is at least partially contoured.

3. the first section (4.1) and the fifth section (4.5) are designed in particular to be form-fitted by folding, beading, rolling or crimping at least one of the sections (4.1, 4.5); and / or 3. The cell connector (1) according to claim 1 or 2, characterized in that the first section (4.1) and the fifth section (4.5) are designed for frictional and / or material bonding, in particular by riveting, screwing, welding and / or gluing the sections (4.1, 4.5) together.

4. 3. The cell connector (1) according to claim 1 or 2, characterized in that the second section (4.2) has a cutout, in particular a substantially rectangular cutout, for forming a welding window (13) extending through the second section (4.2) in the thickness direction (D), the long side of the cutout extending in the longitudinal direction (L).

5. The cell connector (1) according to claim 1 or 2, characterized in that the web (14) has at least one perforation (15), in particular the web (14) has a thickness in the thickness direction (D) that is smaller than the thickness of the strip-shaped element (4), and / or the web (14) is corrugated in the width direction (B).

6. 3. A cell connector (1) according to claim 1 or 2, characterized in that at least one strip-shaped element (4) has a connection flange (16) extending in the longitudinal direction (L) and extending in the width direction (B) away from the second section (4.2) and / or the fourth section (4.4) for contact-connecting the strip-shaped element (4) to a current-carrying component arranged on the strip-shaped element (4).

7. 3. The cell connector (1) according to claim 1 or 2, characterized in that, in the folded state of the at least one strip-shaped element (4), the second section (4.2) is at least partially curved in the thickness direction (D) and / or at least one half (5.1, 5.2) of the closure element has a contour (22) extending in the thickness direction (D) in the connected state of the closure element, in order to increase the pressing force (F) of the first clamping surface (6.1) and the second clamping surface (6.2) acting in the thickness direction (D) on the conductor (2) and / or Litz wire (3) arranged in the accommodation portion (9).

8. 3. A cell connector (1) according to claim 1 or 2, characterized in that the at least one strip-shaped element (4) is formed completely from an electrically conductive material (M), in particular a metal or metal alloy, preferably a metal plate, or the at least one strip-shaped element (4) is formed at least partially from an electrically conductive material (M), in particular a metal or metal alloy, preferably a metal plate, and at least partially from a current-insulating material (I), the insulating material (I) preferably forming at least the fourth section (4.4).

9. 3. A method for contacting at least two galvanic cells with at least one cell connector (1) according to claim 1 or 2, comprising: At least the following method steps: - mutually adjusting the conductors (2) and / or Litz wires (3) to be connected; The fourth section (4.4) is at least partially on the side opposite the receiving section (9) (S １ ) on the cover (17) of at least one galvanic cell and / or at least one conductor (2) and / or at least one Litz wire (3) are supported on the side (S) of the fourth section (4.4) facing the receiving part (9). ２ arranging the cell connector (1) relative to the conductor (2) and / or Litz wire (3) so that it is placed on the - folding the first section (4.1) and the second section (4.2) by the folding axis (8) extending in the width direction (B) through the third section (4.3) to bring the strip-shaped element (4) into a folded state; - closing the closure element; - welding the conductors (2) and / or litz wires (3) to be connected or welding at least a part of the cell connector (1) to the conductors (2) and / or litz wires (3) to be connected, in particular by means of at least one weld seam (18) extending in the longitudinal direction (L), preferably using laser welding as welding method; The method, characterized by:

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